The New York Academy of Sciences is sponsoring a 2.5-day conference, titled "Oral Tolerance: Mechanisms and Applications." This conference has been organized by Drs. Lloyd Mayer, Howard L. Weiner and Warren Strober, and will be held in New York City during fall, 2003. Oral tolerance is a long recognized mechanism of inducing immune tolerance. These studies have resulted in both an enhanced understanding of the underlying processes involved in tolerance induction as well as therapeutic schemes to treat a variety of mouse models of aberrant immune responses and selected human diseases. Since the last conference on oral tolerance organized by us in 1995, there has been an explosion in the understanding of potential mechanisms of oral tolerance through the use of mouse models, a greater appreciation for the existence of novel regulatory T cells, and a clearer view of the way in which the mucosal immune system responds. It is the goal of this conference to bring these three areas together and to review of our current understanding of the basic mechanisms of oral tolerance and its application to disease states. The first conference was enormously successful in focusing in on the areas that required development and further explanation. It is time to reconvene, bring in scientists who have made major strides in this area as well as investigators who have defined novel immuno-regulatory pathways in mucosal immune responses. Most importantly, we will set aside one session to review clinical trials in human disease and have a round-table discussion involving all of the participants to determine why there has been little success in these trials. The audience, consisting of a diverse group of basic and clinical researchers in the areas of immunology, gastroenterology and autoimmunity, will gain the latest information on mechanisms of oral tolerance, new applications, and results in human trials, and have an opportunity to interact with researchers in their own and other fields. [unreadable] [unreadable]